closes#9786
- Make GET request when url has no provider match
- The HEAD request was made in order to send less data over the wire when
checking for redirects for urls that do not have an oembed provider
match. We are now going to look for provider metatags withing the
response of the request - rather than making a HEAD followed by a GET if
no redirect is found, this condenses that to a single request.
- Try to get OEmbed data from tag if no provider
- Here we parse the HTML response of the resource and look for a link tag
that will give us the oembed resource url which we can use to fetch the
embed html
refs https://github.com/TryGhost/Ghost/issues/9724
- perform a HEAD request on a url if we don't find a matching provider, following any redirects until we hit success response before looking up providers for the resulting url
refs https://github.com/TryGhost/Ghost/issues/9623
- add `oembed-parser` module for checking provider availability for a url and fetching data from the provider
- require it in the `overrides.js` file before the general Promise override so that the `promise-wrt` sub-dependency doesn't attempt to extend the Bluebird promise implementation
- add `/oembed` authenticated endpoint
- takes `?url=` query parameter to match against known providers
- adds safeguard against oembed-parser's providers list not recognising http+https and www+non-www
- responds with `ValidationError` if no provider is found
- responds with oembed response from matched provider's oembed endpoint if match is found
